1. Technical Field
The present invention relates to a method of fabricating planar optical waveguides in one chamber and, more particularly, to a method of fabricating planar optical waveguides in which consecutive processes are performed in one chamber while only changing reactive etch gases.
2. Related Art
In general, formation of optical waveguides of a planar waveguide device by etching is the core process for fabricating the planar waveguide device, and is accompanied by several processes.
First, after a cladding layer and a core layer are deposited on a planar substrate, an etch mask layer of predetermined material is deposited on the core layer and a photoresist PR is deposited on the etch mask layer to thus form a photoresist pattern using photolithography. Next, a mask pattern is manufactured by wet etching or dry etching the photoresist. After removing the mask layer remaining on the mask pattern, the core layer is etched according to an etch mask pattern, thereby forming an optical waveguide. An upper cladding layer is deposited on the optical waveguide.
However, this conventional etch mask pattern fabrication method requires PR ashing, etch mask pattern formation, waveguide pattern formation, and residual etched mask removal as special processes, which complicates process steps. Also, each step is performed in a different chamber to which a different reactive gas is supplied, which causes the substrate to be frequently exposed to the outside.